import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.Scanner;

public class TcpEchoClient {
    private Socket socket = null;

    public TcpEchoClient(String serverIp, int serverPort) throws IOException {
        //创建socket的时候, 就要和服务器建立连接
        //当我们new这个对象的时候, 操作系统内核就开始进行 "三次握手" 的具体细节, 完成建立连接的过程了
        socket = new Socket(serverIp, serverPort);
    }

    public void start() {
        Scanner scanner = new Scanner(System.in);
        try (InputStream inputStream = socket.getInputStream();
             OutputStream outputStream = socket.getOutputStream()) {
            //从服务器上读取响应, 然后显示到界面上
            PrintWriter printWriter = new PrintWriter(outputStream);
            Scanner scannerNetwork = new Scanner(inputStream);
            while (true) {
                //1.从控制台读取用户输入内容
                System.out.print("-> ");
                String request = scanner.next();
                //2.发送给服务器
                printWriter.println(request);
                printWriter.flush();
                //3.读取响应
                String response = scannerNetwork.next();
                //4.在界面上显示内容
                System.out.println(response);
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    public static void main(String[] args) throws IOException {
        TcpEchoClient client = new TcpEchoClient("127.0.0.1", 9091);
        client.start();
    }
}
